Racer guys know what's up. Go fast vs. go far, the goals are different but the techniques draw on similar knowledge.
If you were to add some kind of cowling, maybe just a sheet of aluminum, to shroud the intake at the exhaust header a little more, I think you would see an improvement on your intake temps.
Absolutely start a garage page for your ride. It's too bad we don't have numbers for what you were getting at the start, but pushing from low 30s to low 40s is huge.
For some inspiration, take a look at
The Donkey CRX. He's got a ride similar to yours and has pushed it to cartoonishly high fuel efficiency records. I think he has the better engine for it but if you're as good at wrenching as all that, that shouldn't be a big problem for you.
Is anyone besides me a little sad the new tire spats don't say "Outfront?"